Australian Sky & Telescope - May 2018

Leo P

I Zwicky

18

Little

Cub

Small
Magellanic
Cloud Leoncino

SBS

0335-

052W

J0811+

4730

100

101

102

103

104

105

106

107

108

109

1010

1011

15

%

0.04

2.6

%

0.2

2.6

%

0.00004

1. 8

%

0.001

1.7

%

0.5

2.3

%

0.01

2.3

%

0.0008

Shown below are parameters for our home galaxy, one of its small neighbours (the Small Magellanic Cloud), and the oxygen-

poor galaxies discussed in the article. Solar values serve as the benchmark for the oxygen abundances, and masses are

approximate to within a factor of 10. Although the dwarfs churn out fewer stars per year than the Milky Way (second row),

they also have a lot less mass to work with (bottom). The Milky Way’s gas mass here includes the disk and bulge.

http://www.skyandtelescope.com.au 31